Synergistically achieving ultra-broadband tunable near-infrared emission enhancement through anion substitution and defect passivation for multiple applications

Near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) are an emerging type of broadband NIR light source, yet simultaneously achieving ultra-broadband emission and high luminous efficiency remains a key challenge. Herein, we developed a series of Cr 3+ , Ni 2+ , F - co-doped magnesium gallate oxyfluoride phosphors. Compared with non-F - -doped counterparts, the resultant phosphors exhibited an 8.17-fold enhancement in photoluminescence intensity, with the internal quantum efficiency (IQE) significantly increasing from 22.6 % to 74.6 %. F⁻ doping reduces the local crystal field symmetry around Cr³⁺ ions, attenuates the parity-forbidden effect of d-d transitions, and passivates oxygen vacancy defects, thus serving as the primary mechanism for luminescence enhancement. Importantly, at 373 K, MGOF:Cr 3+ ,Ni 2+ retained 71.7 % of its room-temperature emission intensity. Ultimately, the high-efficiency, broadband near-infrared emission from MGOF:Cr 3+ , Ni 2+ was successfully employed in night vision, biological tissue detection, non-destructive inspection, and food quality monitoring applications. The proposed synergistic dual strategy of anion substitution and vacancy passivation provides robust design principles for the rational fabrication of advanced high-performance luminescent phosphors.